Hinge arm



FIG. 1 is a top view of our novel hinge arm;

FIG. 2 is a bottom view thereof;

FIG. 3 is an elevation view thereof, from the bottom of FIG. 1;

FIG. 4 is an elevation view thereof, from the top of FIG. 1; and

FIG. 5 is a side elevation view thereof, the opposite side being a mirror image. 

The ornamental design for a hinge arm, substantially as shown and described. 